1. Field of the Invention
The present invention relates to a device by means of which the shape of a deficient-edged board, beam, or other such timber can be determined and which can be used, with the aid of a computer, to control the board-directing device and the setting of the width in an edge-trimming device so that an optimal quantity of timber is obtained from the board to be trimmed.
2. DESCRIPTION OF THE PRIOR ART
It is prior known, e.g. from the Swedish Pat. No. 307,443 to pass the board by light sources that illuminate the board and provide pulses from the sawn surface as well as from the wanes of the board, said pulses being received by detectors positioned on the opposite side of the board to be measured. The device is suitable for use as positioned directly in the trimming line, where optimization is carried out by adjusting the saw blades. Also, the relatively long distance between the measuring point and the trimming blades, as well as an eventually necessary stopping of the board, tends to increase the inaccuracy of the device.
In order to minimize the distance between the measuring point and the trimming point, it has been suggested to transfer the board laterally upon measuring. In such device it is known to use instead of light sources, a measuring head positioned closely onto the surface of the board and blowing pressurized air onto the board. Detectors sensing reflected air can hereby detect whether the board surface is undefected or not. The object of the invention is to provide a device for determining the shape of a deficient-edged board, suitable for use especially in edge-trimming systems in which a board is optimized on a measuring line parallel to the trimming line, the measuring information providing the necessary data and controlling the selection before the transversal transfer, whereby the board maintains its direction when transferred to the trimming line. Such a transversal mechanism and trimming line have been disclosed in the U.S. application, Ser. No. 709,389, filed on July 28, 1976, and hereby incorporated by reference.